In such a conventional game program, the items to be used in a virtual world in the game, such as cards, arms and magic, are transferred by buying or selling at an item shop set in the virtual world with currency or points passing in the virtual world, and the price of transfer is always fixed.
But, the virtual world in such a system is widely different from the actual world where prices are always changed. Owing to this reason, the reality of the game is spoiled and the fun of the game is decreased.
Then, developments of game program and a game machine wherein the price of the item is also fluctuated in the game, thereby increasing reality and fun of the game, are still awaited.